Goitrogenic activity of p-coumaric acid in rats
The effects of three natural phenolic acids (caffeic, ferulic, and p-coumaric) on the rat thyroid gland were examined in a 3-week oral-treatment study. Forty male Wistar albino rats, divided into groups of 10 rats each and fed iodine-rich diet, were administered by gastrointestinal tube saline (control), caffeic acid, ferulic acid, or p-coumaric acid at a dose level of 0.25 μmol/kg/day for 3 weeks. The mean absolute and relative thyroid weights in caffeic, ferulic, or p-coumaric acid groups were significantly increased to 127 and 132%, 146 and 153%, or 189 and 201% compared to control value, respectively. Histological examination of the thyroids of p-coumaric acid group revealed marked hypertrophy and/or hyperplasia of the follicles. Caffeic or ferulic groups showed slight to moderate thyroid gland enlargement. Thyroid lesions in p-coumaric acid group were associated with significant increases in cellular proliferation as indicated by [3H]thymidine incorporation. In addition, the goitrogenic effect of p-coumaric acid was further confirmed by significant decreases (50%) in serum tri-iodothyronine (T3) and thyroxine (T4), and a parallel increase (90%) in serum thyroid stimulating hormone (TSH) compared to control group. These results indicate that administration of p-coumaric acid at relatively high doses induces goiter in rats. © 2003 Wiley Periodicals, Inc.
Khelifi-Touhami, Fatima; Taha, Ragia A.; Badary, Osama A.; Lezzar, Alkassem; and Hamada, Farid M.A., "Goitrogenic activity of p-coumaric acid in rats" (2003). Pharmacy. 157.